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Learning About Obesity

BMI chart (metric)

What is obesity?

Obesity means having an unhealthy amount of body fat. This puts your health in danger. It can lead to other health problems, such as type 2 diabetes and high blood pressure.

How do you know if your weight is in the obesity range?

To know if your weight is in the obesity range, your doctor looks at your body mass index (BMI) and waist size.

BMI is a number that is calculated from your weight and your height. To figure out your BMI for yourself, you can use an online tool, such as https://www.diabetes.ca/managing-my-diabetes/tools---resources/body-mass-index-(bmi)-calculator on the Diabetes Canada website.

If your BMI is 30.0 or higher, it falls within the obesity range. Keep in mind that BMI and waist size are only guides. They are not tools to determine your ideal body weight.

What causes obesity?

When you take in more calories than you burn off, you gain weight. How you eat, how active you are, and other things affect how your body uses calories and whether you gain weight.

If you have family members who have too much body fat, you may have inherited a tendency to gain weight. And your family also helps form your eating and lifestyle habits, which can lead to obesity.

Also, our busy lives make it harder to plan and cook healthy meals. For many of us, it's easier to reach for prepared foods, go out to eat, or go to the drive-through. But these foods are often high in saturated fat and calories. Portions are often too large.

What can you do to reach a healthy weight?

Focus on health, not diets. Diets are hard to stay on and don't work in the long run. It is very hard to stay with a diet that includes lots of big changes in your eating habits.

Instead of a diet, focus on lifestyle changes that will improve your health and achieve the right balance of energy and calories. To lose weight, you need to burn more calories than you take in. You can do it by eating healthy foods in reasonable amounts and becoming more active, even a little bit every day. Making small changes over time can add up to a lot.

Make a plan for change. Many people have found that naming their reasons for change and staying focused on their plan can make a big difference. Work with your doctor to create a plan that is right for you.

  • Ask yourself: "What are my personal, most powerful reasons for wanting this change? What will my life look like when I've made the change?"
  • Set your long-term goal. Make it specific, such as "I will lose x kilograms."
  • Break your long-term goal into smaller, short-term goals. Make these small steps specific and within your reach, things you know you can do. These steps are what keep you going from day to day.

Talk with your doctor about other weight-loss options. If you have a BMI in a certain range and have not been able to lose weight with diet and exercise, medicine or surgery may be an option for you. Before your doctor will prescribe medicines or surgery, he or she will probably want you to be more active and follow your healthy eating plan for a period of time. These habits are key lifelong changes for managing your weight, with or without other medical treatment. And these changes can help you avoid weight-related health problems.

How can you stay on your plan for change?

Be ready. Choose to start during a time when there are few events like holidays, social events, and high-stress periods. These events might trigger slip-ups.

Decide on your first few steps. Most people have more success when they make small changes, one step at a time. For example, you might switch a daily candy bar to a piece of fruit, walk 10 minutes more, or add more vegetables to a meal.

Line up your support people. Make sure you're not going to be alone as you make this change. Connect with people who understand how important it is to you. Ask family members and friends for help in keeping with your plan. And think about who could make it harder for you, and how to handle them.

Try tracking. People who keep track of what they eat, feel, and do are better at losing weight. Try writing down things like:

  • What and how much you eat.
  • How you feel before and after each meal.
  • Details about each meal (like eating out or at home, eating alone, or with friends or family).
  • What you do to be active.

Look and plan. As you track, look for patterns that you may want to change. Take note of:

  • When you eat and whether you skip meals.
  • How often you eat out.
  • How many fruits and vegetables you eat.
  • When you eat beyond feeling full.
  • When and why you eat for reasons other than being hungry.

When you stray from your plan, don't get upset. Figure out what made you slip up and how you can fix it.

Can you take medicines or have surgery to lose weight?

If you have a BMI in a certain range and have not been able to lose weight with diet and exercise, medicine or surgery may be an option for you.

If you have a BMI of at least 30.0 (or a BMI of at least 27.0 and another health problem related to your weight), ask your doctor about weight-loss medicines. They work by making you feel less hungry, making you feel full more quickly, or changing how you digest fat. Medicines are used along with diet changes and more physical activity to help you make lasting changes.

If you have a BMI of 40.0 or more (or a BMI of 35.0 or more and another health problem related to your weight), your doctor may talk with you about surgery. Weight-loss surgery has risks, and you will need to work with your doctor to compare the risk of having obesity with the risks of surgery.

With any option you choose, you will still need to eat a healthy diet and get regular exercise.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Where can you learn more?

Go to https://www.healthwise.net/patientEd

Enter N111 in the search box to learn more about "Learning About Obesity".

Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.